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31.
Increasing attention has been paid to the peripheral gate-oxide integrity degradation of Flash memory devices that is induced by the tunnel-oxide nitridation. In this letter, the mechanisms of tunnel-oxide nitridation-induced degradation are characterized. We report that both a local oxide thinning effect and nitrogen residue will impact the integrity of gate-oxide. Minimizing the local thinning effect with an in situ steam generation (ISSG) oxidation process and removing the nitrogen residues from the silicon wafer surface by either an additional sacrificial oxide process or over-dip are proven to be useful in recovering the gate-oxide integrity. An optimum approach with the tunnel-oxide nitridation is proposed in this work that results in comparable or even better gate-oxide property than other approaches that have no tunnel-oxide nitridation process.  相似文献   
32.
High-performance, reliable, and robust products with a short development schedule are general design aims. FACE was developed to achieve these goals, including the organization of a design flow, a frequency-driven information analyzer, compiler techniques (code generator and instruction optimization), and a hierarchical object design library. This paper explores the design space of a retargetable compiler and a reconfigurable hardware, which combine both software and hardware reprogrammability. The environment, FACE, we have developed allows us to quickly move the functions between software and hardware in a state of flux. Finally, it generates the application specific integrated processor (ASIP) and a compiler for the new ASIP architecture. The case study is considered which demonstrates the efficiency in ASIP design of FACE.  相似文献   
33.
Jeng  J.H. Shyu  J.R. 《Electronics letters》2000,36(8):716-717
In fractal image compression, the mean squared error (MSE) computations of the eight orientations of the domain blocks can be reduced into two groups of inner products in the frequency domain. A very simple classification scheme is presented for reducing the two groups of computations into one, which makes the encoder up to 4.7 times faster  相似文献   
34.
The application of Reed-Solomon codes in slow frequency-hopped systems has been extensively studied. Earlier investigations assumed an infinite interleaving length and considered partial-band noise jammers only. This paper extends previous efforts by analyzing the effect of finite interleaving length and the impact of band multitone jammers. We also explain why two-threshold (2T) erasure-insertion methods (EIM) are needed and examine their performance. Numerical results are presented to compare the effectiveness of the EIM and jammer types and to study the relationships among the hop rate, the interleaver size, and the code rate. The use of 2T-EIM necessitates the estimation of several additional channel and signal parameters. Simple and effective estimation algorithms are provided as well  相似文献   
35.
To study DNA allostery, quantitative DNase I footprinting studies were carried out on a newly designed peptide His‐Hyp‐Lys‐Lys‐(Py)4‐Lys‐Lys‐NH2 (HypKK‐10) containing the XHypKK (Hyp = hydroxyproline) and polyamide motifs. The interconnection of DNA footprints of peptides HypKK‐10 and the parent peptide PyPro‐12 supports the proposal that interaction network cooperativity is preferred in DNA‐peptide interactions between multiple recognition sites. A simple method of determining interstrand bidentate interactions between the peptide moieties and DNA bases is introduced. It is envisaged that interstrand bidentate interactions also participate in the relay of conformational changes to recognition sites on the complementary strands. Circular dichroism studies of the titration of peptide HypKK‐10 with an oligonucleotide duplex indicate that this peptide binds in a dimeric fashion to DNA in the minor groove. This work may prompt the design of new DNA binding ligands for the study of DNA‐peptide allosteric interactions and DNA interaction network.  相似文献   
36.
37.
Integrated circuit (IC) wafer fabrication systems can be characterized as discrete event systems. Petri nets are tools that have been successfully used to model and analyze such systems. This paper reports a project of applying Petri net methodologies to detailed modeling, qualitative analysis, and performance evaluation of the etching area in a real-world IC wafer fabrication system located in Taiwan's Hsinchu Science-Based Industrial Park, To tackle the problem of building a large and complex system model, a synthesis technique is used. The resultant extended net model is checked for important qualitative properties in manufacturing. A simple control policy for deadlock prevention is proposed. To obtain performance measures, simulation is used. The simulation result shows that except a small number of machines, the errors between the simulated and actual utilizations are less than 5%, The validated model can be used to answer many “what-if” questions, such as predicting the maximal throughput and bottleneck machines  相似文献   
38.
The Universal Mobile Telecommunications System (UMTS) offers IP-based multimedia applications and services with end-to-end Quality of Service (QoS) guarantee. The key component providing these services is the IP Multimedia Subsystem (IMS) that uses Service-Based Local Policy (SBLP) management for QoS control. To support end-to-end QoS, the UMTS IMS network should be scalable, reliable and flexible in policy deployment and enforcement, characteristics that are not found in single-domain policy architecture. A hybrid policy architecture is proposed, in which a hierarchical architecture is applied to the multi-domain environment in a single operator UMTS IMS network, while a peering architecture is employed in a multi-operator UMTS IMS network. The proposed multi-domain policy architecture potentially minimizes the session setup delay and policy exchange traffic while maximizing network scalability.  相似文献   
39.
A cluster-based maximum-likelihood sequence estimator (MLSE) for nonlinear channels was described, which consists of a clustering network and an MLSE implemented by the Viterbi algorithm. The cluster-based MLSE can be used for digital communication through nonlinear finite-length channels because channel mapping estimation is used instead of channel estimation in the conventional MLSE. The clustering network of the cluster-based MLSE, which estimates the channel mapping between the signal input vectors and the noiseless channel outputs, is a supervised network and requires a training sequence. We propose a blind channel mapping estimator to estimate the channel mapping without using the training sequence. The blind channel mapping estimator has a clustering block and a mapping block. The clustering block estimates the channel outputs, which represent the channel mapping, subject to an unknown permutation operation because no training sequence is utilized. That permutation operation is resolved by the mapping block, and therefore, the channel mapping is obtained. Introducing the blind channel mapping estimator into the cluster-based MLSE, a blind cluster-based MLSE for nonlinear channels can be done. Computer simulations of the blind channel mapping estimator and the blind MLSE for nonlinear channels are presented  相似文献   
40.
This paper presents a deterministic method to establish the scattering-center model for complex radar targets. By this method, high frequency techniques including physical optics, physical theory and diffraction and shooting and bouncing rays are used to establish scattering centers. Numerical results show that, by using this method with only single-frequency scattering centers at large aspect increments, the RCS pattern at finer aspect increments is well reconstructed; besides, it can be extended to predict the RCS pattern at any frequency of interest in a required narrow bandwidth. Good agreement between direct RCS calculation, scattering-center model and measured results is obtained  相似文献   
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